A variety of medical devices are used for chronic, i.e., long-term, delivery of therapy to patients suffering from a variety of conditions, such as chronic pain, tremor, Parkinson's disease, epilepsy, urinary or fecal incontinence, sexual dysfunction, obesity, spasticity, or gastroparesis. As examples, electrical stimulation generators are used for chronic delivery of electrical stimulation therapies such as cardiac pacing, neurostimulation, muscle stimulation, or the like. Pumps or other fluid delivery devices may be used for chronic delivery of therapeutic agents, such as drugs. Typically, such devices provide therapy continuously or periodically according to parameters contained within a program. A program may comprise respective values for each of a plurality of parameters, specified by a clinician. The devices may be implantable medical devices that receive the program from a programmer controlled by the clinician.
Examples of such implantable medical devices include implantable fluid delivery devices, implantable neurostimulators, implantable cardioverters, implantable cardiac pacemakers, implantable defibrillators, cochlear implants, and others that now exist or may exist in the future. These devices are intended to provide a patient with a therapeutic output to alleviate or assist with a variety of conditions. Typically, such devices are implanted in a patient and provide a therapeutic output under specified conditions on a recurring basis.
One type of implantable fluid delivery device is a drug infusion device which can deliver a fluid medication to a patient at a selected site. A drug infusion device may be implanted at a location in the body of a patient and deliver a fluid medication through a catheter to a selected delivery site in the body. Drug infusion devices, such as implantable drug pumps, include fluid reservoirs that may be self-sealing and may be accessible through ports. A drug infusion device may be configured to deliver a therapeutic agent from the fluid reservoir to a patient according to a therapy program, which may, for example, specify a rate of delivery by the IMD of a fluid delivered to the patient.
Programmable implantable medical devices are typically programmed using an external programming device, sometimes known as a controller or programmer, which can communicate with the implanted medical device through well known techniques such as wireless telemetry. An external controller, or programmer, can be used by a medical professional, for example, to change the therapeutic regimen by increasing or decreasing the amount of fluid medication delivered to the patient. Typically, a medical professional interfaces with the external controller or programmer to set various parameters associated with the implantable medical device and then transmits, or downloads, those parameters to the implanted medical device. The external device may also record other information important to the delivery of the therapy. Some information may be stored in the implantable medical device and/or the external programming device. Such information may include patient information, implanted device information such as model, volume, implant location, length of catheter or lead, and other information specific to different devices.